10 Diagnostic procedures and endoscopic measures for bile duct stones FRIEDRICH HAGENMtJLLER HENNING SCHWACHA

INTRODUCTION The management of common bile duct (CBD) stones is in a continuing state of evolution. The recent introduction and widespread acceptance of laparoscopic cholecystectomy has focused attention on non-operative methods for treating CBD stones. The main therapeutic approaches for dealing with CBD stones are endoscopic retrograde cholangiography (ERC) and percutaneous cholangiography. Therapeutic methods that can be used with both techniques will be outlined in this chapter. An attempt will be made to describe the overall management of CBD stones and a proposed sequence of interventions will be outlined. The role of ERC in relation to elective cholecystectomy and traditional surgery will also be discussed. Direct cholangiography is the diagnostic modality of choice for CBD stones. The natural history of gallstone disease suggests that for the most part it is a benign condition. Mok et al (1986) estimated that patients with symptomatic stones have the stone for 8.0 k 5.1 years before they begin to experience symptoms. Similarly Wolpers (1986) confirmed the benign nature of gallstone disease. He followed a group of patients with asymptomatic gallstones for a period of up to 30 years (mean 13.5 years). Biliary pain occurred in 29% of patients; 4% of patients developed acute cholecystitis and 5.5% acute pancreatitis. When stones are present in the gallbladder it can usually be assumed that any coexistent CBD stones are of gallbladder origin (Sieg et al, 1986). In contrast, stones that form in the bile duct are usually pigment stones, thought to arise following the deconjugation of bile by bacteria producing B-glucuronidase (Skar et al, 1989). CBD stones may be asymptomatic,or present as biliary colic, jaundice, cholangitis or pancreatitis. In the past most stone were asymptomatic, discovered at cholecystectomy and CBD exploration. Neoptolemos et al (1987) found that over a 5-year period 438 of 2500 (18%) patients undergoing surgery for gallstone disease had CBD stones. Fifty (2%) presented with Baillitire’s

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acute cholangitis. This is lower than the normally published incidence of 6-9% (Saik et al, 1975). It is difficult to estimate the number of patients with CBD stones who present with acute pancreatitis. However, the incidence of CBD stones at the time of urgent operation for acute pancreatitis has been reported to be as high as 63-78% (Kelly, 1980; Stone et al, 1981). In contrast the proportion of patients with CBD stones operated on at a later time varies from 3 to 33% (Kelly, 1980; Stone et al, 1981). Furthermore, stool examination during an attack of acute pancreatitis will demonstrate stones in 85 - 95% of patients, while faecal stones are found in only 10% of patients with gallstones but no associated pancreatitis (Acosta and Ledesma, 1974). All these studies indirectly support Opies’ hypothesis of gallstone migration and impaction as the major cause of biliary pancreatitis. Patients with suspected pancreaticobiliary disorders presenting with pain, jaundice or pancreatitis are usually clinically assessed followed by laboratory investigations and ultrasonography. It must be borne in mind that some patients may be critically ill and that there is no time for orderly investigation followed by therapy. In particular, we are referring to patients with severe pancreatitis or cholangitis, or features of both. Patients with Charcot’s triad should be resuscitated and arrangements made for definitive therapy. ULTRASONOGRAPHY

AND COMPUTED

TOMOGRAPHY

Usually ultrasonography is the initial imaging procedure in patients suspected of choledocholithiasis. It is a safe, readily available, and relatively inexpensive procedure. However, the reported sensitivity of this technique for CBD stones ranges from 19 to 44% (Thomas et al, 1982; Cooper et al, 1985; Cronin, 1987; O’Connor et al, 1986). However, when CBD stones are detected on ultrasonography, the finding is very specific (O’Connor et al, 1986). It should also be noted that the CBD may not be dilated in a significant number of patients (24-36%) (Venu et al, 1983). Abdominal computed tomography is also not particularly sensitive for detecting CBD stones. Baron (1987) reported a sensitivity of 26% for CBD stones with this modality. ERC AND PERCUTANEOUS TRANSHEPATIC CHOLANGIOGRAPHY (PTC)

The definitive diagnosis of CBD stones can be made only at direct cholangiography and cholangioscopy, the former being the more widely practised technique. This can be accomplished either by percutaneous puncture of the biliary tree and instillation of contrast, or endoscopic cannulation of the papilla of Vater and retrograde cholangiography. The beauty of these procedures is that diagnostic and therapeutic intervention can be performed concomitantly. Ideally both techniques should be available in an institution and should be used in a cooperative manner.

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Figure 1. (a) Large stone in the common bile duct. (b) Extraction of the stone with Dormia basket after endoscopic papillotomy. (c) Common bile duct after complete stone clearance.

After diagnostic ERC, the next step in the diagnosis of CBD stones is sphincterotomy. The stones can now be removed from the CBD using a variety of different baskets or balloons (Figure 1). Approximately 80-90% of stones can be cleared from the CBD following sphincterotomy (Hagenmtiller and Classen, 1982). This procedure is associated with a low incidence of complications and mortality (Hagenmtiller and Classen, 1982). Incomplete clearance of the duct has been associated with

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Figure 2. (a) Large bile duct stone. Conventional Dormia basket fails to grasp the stone. (b) The stone has been trapped in a large hthotriptor basket. The endoscope is removed. (c) Mechanical lithotripsy failsthe stone is too hard. (d,e) Disruption of the lithotriptor basket. (f) A nasobiliary drainage tube is inserted; extracorporeal shockwave hthotripsy is performed. (g) Multiple stone fragments after ESWL. The fragments passed spontaneously into the duodenum.

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increased morbidity and major complications (3-8%) (Neoptolemos et al, 1987; Kullman et al, 1989). In the non-strictured CBD, calculus size is the main reason for failure of stone extraction. Stones greater than 1.5 cm in diameter may prove difficult to remove with standard baskets and balloons. In the situation where a large stone is detected at ERC, mechanical lithotripsy can be undertaken. Two types of mechanical lithotriptors are currently available: one can be used through an endoscope (Olympus Corporation, Lake Placid, New York) and one can be used without an endoscope (Wilson-Cook Medical, Winston-Salem, North Carolina). One advantage of the latter instrument is that it can be used with conventional stone extraction baskets, avoiding the problem of stone impaction which required surgery in the past. The reported success rate of mechanical lithotripsy is 20-94%, with a slightly lower success when stones are greater than 2.5 cm (70%) (Classen et al, 1988; Schneider et al, 1988; Maydeo and Soehendra, 1990; Siegel et al, 1990b). The reason for failure of this technique is usually inability properly to snare the stone in the basket. The process of mechanical lithotripsy has not been associated with any complications per se. Most reported complications are usually due to the sphincterotomy performed prior to attempts at stone extraction. When this technique fails, other modalities must be used (Figure 2). If anatomical reasons do not allow an endoscopic cannulation of the papilla of Vater, nor sphincterotomy and extraction of stones, the next diagnostic step is PTC. To show CBD stones a catheter has to be inserted transhepatically into the CBD. To provide a larger biliocutaneous tract, dilatation with special drains has to be performed. Through the artificial biliocutaneous fistula the CBD stones can either be removed transhepatitally using special baskets or after fragmentation transpapillary can be pushed into the duodenum. Stokes and Clouse (1990) reported a 93% success rate in percutaneous transhepatic extraction of CBD stones. PTC can be combined with other modalities of stones fragmentation (e.g. electrohydraulic lithotripsy). ELECTROHYDRAULIC

LITHOTRII’SY

Originally developed for industrial use in Russia, this apparatus consists of a single current generator and a probe with bipolar electrodes at its tip. The spark discharge produces a shockwave in a fluid medium. Any structure in the path of the wave will absorb shockwave energy, develop a pressure gradient, and fragment. Burhenne (1975) was the first to apply this technology for fragmentation of retained bile duct stones. Early applications of this technology were hampered by the inability to monitor probe position under direct vision. This resulted in a significant number’ of complications (haemorrhage and perforation) (Koch et al, 1977). Siegel et al (1990a) used the probe in conjunction with a balloon to avoid damage to the bile duct wall. Liguory et al (1987) reported on the successful

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(b) Figure 3. (a) Choledocholithiasis in a patient after Billroth II resection of the stomach. Conventional stone extraction failed. (b) Peroral cholangioscopy with a mother and baby scope system. The stone is approached with the cholangioscope and destroyed by electrohydraulic lithotripsy under visual control.

use of this modality under direct vision. Since that time there have been many reports of electrohydraulic lithotripsy used with peroral (Figure 3) or percutaneous (Figure 4) cholangioscopy. LASER

LITHOTRIPSY

At high levels of energy and short pulsations, laser light energy is converted not only into heat but also into mechanical energy. El1 et al (1986) first reported on the use of a flash lamp pulsed neodymium yttrium-aluminiumgarnet laser. They treated nine patients with no untoward effect; however, there is possibility of thermal injury to the bile duct wall with this instrument. A flash lamp excited dye laser has recently been introduced. This laser has several advantages. Because its wavelength can be altered, one at which gallstone destruction is more efficient can be used and, owing to the short bursts of energy used, very little heat is produced. The risk of perforation is so low that in the future this instrument may be used under fluoroscopic

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(cl Figure 4. (a) Choledocholithiasis in a patient after gastrectomy. A cholangioscope is approaching the stone via the percutaneous route through a cutaneobiliary fistula. (b) The stone is fragmented by electrohydraulic lithotripsy. The fragments are extracted with a basket. (c) Bile duct free of stones.

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(cl Figure 5. (a) Multiple large stones in the bile duct. Conventional stone extraction failed. ESWL is performed. (b) Multiple fragments after ESWL. (c) Stone-free bile duct after endoscopic extraction of the stone fragments.

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only. Furthermore the thin fibre and possibility of use under fluorocontrol alone could obviate the need for papillotomy and cholangioThese are potential advantages over electrohydraulic lithotripsy. et al (1990) reported on the use of this instrument in 25 patients, with success rate. Further studies using this instrument are awaited.

EXTRACORPOREAL

SHOCKWAVE

LITHOTRIPSY

(ESWL)

This modality of treatment, which uses high pressure waves generated by spark gap, piezoelectric laser or electromagnetic generation, has been shown to be successful for fragmenting large CBD stones. Sauerbruch et al (1989) reported that complete stone disintegration using ESWL could be achieved in a total of 103 of 113 patients with CBD stones. All patients had failed routine endoscopic stone extraction. Fragmentation was achieved in one session (84%)) two sessions (14%) and multiple sessions (1.8%). There was very little morbidity with this procedure (Figure 5). Currently this technology is in a state of flux because less expensive methods are available for the treatment of large CBD stones. Furthermore the rapid spread and enthusiasm for laparoscopic cholecystectomy has usurped the other main use of this technology. Hopefully, newer machines will be introduced that are more efficient and less expensive, and there will be a resurgence of interest in this technology. THE ROLE

OF ENDOPROSTHESIS

PLACEMENT

In any situation where a stone cannot be removed or stone fragments remain following intervention, the placement of a prosthesis will reduce the risk of cholangitis and obstructive jaundice due to impaction. This may be a shortterm measure until swelling and oedema of the papilla and bile duct wall have resolved and the patient’s general condition has improved prior to subsequent endoscopic manoeuvres, or it may be a permanent therapy. Ku1 et al (1989) placed biliary endoprostheses in 105 patients with unextractable CBD stones. In 63 patients the stents were left indefinitely. Patients were followed for l-5 years. Of the 63 patients, 16 had to have their prosthesis replaced because of clogging. The remainder were asymptomatic. Summerfield (1989) demonstrated that if patients had a stent in situ and were given oral dissolution agents, then the majority of stones would become small enough for extraction at a later date. CONTACT

DISSOLUTION

Palmer and Hoffmann (1986) have presented an excellent review of this subject. Mono-octanoin, methyl-tert-butyl-ether and mixtures of bile acids and ethylene diamine tetra-acetic acid (EDTA) have all been shown to dissolve stones in a significant number of patients (26-30%) (Allen et al,

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1985; Palmer and Hoffmann, 1986). However, these modalities have not gained widespread acceptance, partly because they are thought to be tedious to use and are associated with significant side-effects such as diarrhoea, abdominal discomfort, nausea, drowsiness and sedation. At this stage their future is unclear. NEW APPROACHES

TO THE LARGE

STONE

Ultrasonographic lithotripsy (Hwang et al, 1986) and high speed rotational devices (Wholey and Smoot, 1988) have been shown to be effective in vitro, and some of these devices have been used in the occasional patient. These devices are in the developmental stage, however, and their progress will be viewed with interest. SPECIAL

CLINICAL

SITUATIONS

Surgery and CBD stones In the treatment of CBD stones the operative exploration of the CBD in patients after cholecystectomy is nowadays used very seldomly because endoscopic stone extraction is possible in most patients. Exceptions are patients in whom, after other upper gastrointestinal operations, the papilla of Vater cannot be reached endoscopically or where CBD stones are not extractable via endoscopy or alternative measures for stone fragmentation (ESWL, electrohydraulic lithotripsy, etc) are not available in the institution, The operative exploration of the CBD in patients with gallbladder in situ was, before ERCP was introduced, a widespread measure. Operative and endoscopic clearing of the CBD are comparable in effectiveness. Pappas et al (1990) reported a series of 100 CBD explorations in a group of patients with a mean age of 52 years. There was no procedure-related mortality and morbidity. Acute cholangitis Acute cholangitis following choledocholithiasis is a medical emergency and is potentially fatal if untreated. Endoscopic sphincterotomy and removal from the CBD is achieved in 75-83% of cases (Ditzel and Schaffalitzky, 1990; Kassiniadis et al, 1991). Drainage of bile can also be guaranteed by a nasobiliary tube if stone extraction fails. If this procedure also fails, an emergency operation will be necessary for treatment of cholangitis due to CBD stones. Acute pancreatitis In acute pancreatitis of biliary origin, severely ill, high-risk (old) patients should be treated by endoscopic sphincterotomy and stone extraction during the first 72 hours after admission to the hospital. Mortality, morbidity and hospitalization are minimized using this procedure (Shemesch et al, 1990).

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After improvement of the pancreatitis, patients with stones in the gallbladder should undergo cholecystectomy because recurrence of pancreatitis is expected in more than 50% of the patients (Windsor, 1990). Laparoscopic cholecystectomy The technique of laparoscopic cholecystectomy by now is widespread and standardized, so that this method is performed more and more often (Mouret, 1991). The results of laparoscopic and traditional cholecystectomy are comparable (Southern Surgical Group, 1991). If the cystic duct has a diameter of more than 2mm, cannulation and contrasting are possible to show CBD stones. Small-diameter fibrescopes can be used via the cystic duct to perform cholangioscopy and eventually lithotripsy. Today prior to laparoscopic cholecystectomy, in suspicion of choleduocholithiasis, ERC and possibly sphincterotomy with stone removal from the CBD should be performed. Our results in the treatment of choledocholithiasis are shown in Table 1. Table 1. Treatment of choledocholithiasis

(July 1990 to December 1991).

Sphincterotomyktone extraction Sphincterotomy/mechanical lithotripsy and stone extraction Sphincterotomy/ESWL/stone extraction PTUelectrohydraulic lithotripsy Stones not extractable-surgery

No. of patients (n = 125)

%

103 9 2 6 5

82.4 7.2 1.6 4.8 4.0

Over a period of one and a half years (July 1990 to December 1991), 125 unselected patients suffering from choledocholithiasis were admitted. In 103 patients (82.4%) stone removal from the CBD after sphincterotomy was performed. In nine patients (7.2%) mechanical lithotripsy and in two patients ESWL was necessary for stone fragmentation before extraction. Six patients underwent PTC and electrohydraulic lithotripsy under cholangioscopic view. Five patients had to undergo surgery for operative exploration of the CBD (PTC and electrohydraulic lithotripsy were not available at that time). CONCLUSIONS The treatment of CBD stones is in a state of rapid change. There are now many alternative approaches to this problem. Many are equally effective and can be used in conjunction or in sequence. Although difficult to devise, an algorithm is outlined in Figure 6. The approach that is chosen may depend on the expertise in each institution. One wonders whether the treatment of CBD stones is moving out of the domain of surgery, and whether in 1992 it is the obligation of the surgeon to justify an operative approach.

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Endoscopic papillotomy and extraction + Mechanical lithotripsy + Peroral cholangioscopy with electrohydraulic or laser lithotripsy 4 Extracorporeal shockwave lithotriw and extraction

Surgery M

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MEASURES

Prosthesis

Surgery or laser lithotripsy Figure 6. Algorithm

showing instrumental medical management of bile duct stones.

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Maydeo AP & Soehendra H (1990) Management of large bile duct stones. In Barkin J & O’Phelan CA (eds) Advanced Therapeutic Endoscopy, pp 211-229, New York: Raven Press. Mok H, Drtiffel ERM & Rampone WM (1986) Chronology of cholelithiasis: dating gallstones from atmospheric radiocarbon produced by nuclear bomb explosions. New England Journal of Medicine 314: 1075-1077. Mouret P (1991) From the first laparoscopic cholecystectomy to the frontiers of laparoscopic surgery. The future perspectives. Digestive Surgery 8: 124-125. Neoptolemos JP, Davidsen BR, Shaw DE et al (1987) Study of common bile duct exploration and endoscopic sphincterotomy in a consecutive series of 438 patients. British Journal of Surgery 14: 916920. O’Connor HJ, Hamelton I, Ellis WR et al (1986) Ultrasound detection of choledocholithiasis. Prospective comparison with ERCP in the post cholecystectomy patient. Gasfrointestinal Radiology 11: 161-164. Palmer KR & Hoffmann AF (1986) Intraductal monooctanoin for the direct dissolution of bile duct stones. Experience in 343 patients. Gut 27: 19&202. Pappas TN, Slimane TB & Rooks DC (1990) 100 Consecutive common duct explorations without mortality. Annals of Surgery 211: 259-262. Saik RP, Greenburg AG, Farris JM & Peskin GW (1975) Spectrum of cholangitis. American Journal

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JS & Pullano WE (1990a) Endoscopic electrohydraulic lithotripsy. Gastrointestinal Endoscopy 36: 134-136. Siegel JH, Ben-Zui JS & Pullano WE (1990b) Mechanical lithotripsy of common duct stones. Gastrointestinal Endoscopy 36: 351-356. Skar U, Skar AG, Brattke J & Osnes M (1989) B-Glucuronidase activity in the bile of gallstone patients both with and without duodenal diverticula. Scandinavian Journal of Gastrokterology 24: 205-212. Southern Surgical Group (1991) A prospective analysis of 1518 laparoscopic cholecystectomies. New Eneland Journal of Medicine 324: 107%1078. Stokes KR & Clo& ME (1990) Biliary duct stones: percutaneous transhepatic removal. Cardiovascular

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Stone HH, Fabian TC & Dunlop WE (1981) Gallstone pancreatitis: biliary tract pathology in relation to time of operation. Annals of Surgery 194: 305-310. Summerfield JA (1989) Review article: dissolution of gallstones in the biliary tree. Alimentary Pharmacology and Therapeutics 3: 211-221. Thomas MJ, Pellegrini CA & Wey LW (1982) Usefulness of diagnostic tests for biliary obstruction. American Journal of Surgery 144: 102-108. Venu RP, Gienan JE, Touli J et al (1983) Endoscopic retrograde cholangiopancreatography: diagnosis of cholelithiasis in patients with normal gallbladder X-ray and ultrasound studies. Journal of the American Medical Association 249: 758-761. Wholey MH & Smoot S (1988) Choledocholithiasis. Percutaneous pulverisation with a high speed rotational catheter. American Journal of Radiology 150: 129-130. Windsor JA (1990) Gallstone pancreatitis: a proposed management strategy. Australian and New

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Diagnostic procedures and endoscopic measures for bile duct stones.

10 Diagnostic procedures and endoscopic measures for bile duct stones FRIEDRICH HAGENMtJLLER HENNING SCHWACHA INTRODUCTION The management of common b...
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